Analytical Industries GPR-1800 IS ATEX Trace PPM Oxygen Transmitter - Manual (Page 12)

Advanced Instruments, Inc
12
Advanced Galvanic Sensor Technology
All galvanic type sensors function on the same principle and are specific to oxygen. They measure the
partial pressure of oxygen from low PPM to 100% levels in inert gases, gaseous hydrocarbons, helium,
hydrogen and mixed gases
Oxygen, the fuel for this electrochemical transducer, diffusing into the sensor, reacts electrochemically at the
sensing electrode to produce an electrical current output proportional to the oxygen concentration in the gas
phase. The sensor’s signal output is linear over all measuring ranges and remains virtually constant over its
useful life. The sensor requires no maintenance and is easily and safely replaced at the end of its useful life.
Proprietary advancements in design and chemistry add significant advantages to this extremely versatile
oxygen sensing technology. Sensors for low % analysis recover from air to low % levels in seconds, exhibit
longer life and reliable quality. The expected life of our new generation of percentage range sensors now
range from 32 months to ten years with faster response times and greater stability. Another significant
development involves expanding the operating temperature range for percentage range sensors from -30°C
to 50°C. Contact factory for more specific information about your application.
The PPM sensors recover from an upset condition to low PPM level in a matter of few minutes. These
sensors show excellent stability over its useful life.
Electronics
The signal generated by the sensor is processed by state of the art low power micro-processor based digital
circuitry. The first stage amplifies the signal. The second stage eliminates the low frequency noise. The third
stage employs a high frequency filter and compensates for signal output variations caused by ambient
temperature changes. The result is a very stable signal. Sample oxygen is analyzed very accurately.
Response time of 90% of full scale is less than 10 seconds (actual experience may vary due to the integrity
of sample line connections, dead volume and flow rate selected) on all ranges under ambient monitoring
conditions. Sensitivity is typically 0.5% of full scale of the low range. Oxygen readings may be recorded by
an external device via the 4-20 mA or 1-5V signal output.